I think I broke it when I cleaned it

crash2009

I was wondering if anyone knows if its possible to break a pressure gauge while blowing down the boiler or is something else wrong?  Maybe my technique is no good.  My pressuretrol is set to cut-out at 2 lbs.  The guage is a 0-3 lbs.  I wrote the following in a e-mail to my self shortly after finishing so that I could reference it later because I have never done this before.  The automatic water feeder is bypassed to allow just a trickle of fresh water in.  Then the water is boiled and the pressure is allowed to build up to 1.5 lbs.  The valve connecting the garden hose is opened for a 10 count then closed, the pressure pushes all the crap outside.  After all 4 drain valves have been flushed several times, the hose is connected to the skimmer, the gas is shut off, the feeder bypass is still running, and the surface oils are forced through the top.  This process takes about an hour.  Then the process is repeated 4 or 5 times.  Finally, the water level is dropped down to normal, and the oxygen in the water removed, by boiling for 15 minutes.  (pic 668 two of three drain valves) (pic 675 drain to the outside) (pic 679 metal filings picked up with a magnet).  (pic 686 pressuretrol and 0-3 gauge)......I just thought of something.....maybe that gauge stopped working because its mounted sideways?

Rod

Gauge Problems

Hi - I assume you disassembled it and checked for blockage?  I've found it's best to mount gauges, controls etc. on a vertical nipple so they will drain easily if water gets near them.

- Rod

crash2009

No, Rod

I havn't done anything about it yet.  It ran great throughout last night.  I am thinking about how to improve things a bit after I take the 0-3 out for inspection.  I should have a 0-30 anyway, and I need to isolate the 0-3 for when and if I ever do a 10 lb backflush.  Do ya think this would be OK?  (pic 686edited)

crash2009

No, Rod

I havn't done anything about it yet.  It ran great throughout last night.  I am thinking about how to improve things a bit after I take the 0-3 out for inspection.  I should have a 0-30 anyway, and I need to isolate the 0-3 for when and if I ever do a 10 lb backflush.  Do ya think this would be OK?  (pic 686edited)

Rod

Piping for Gauges

Hi- I like the idea of the valve. I have only blown down my boiler once (just drained it the rest of the time) and in that case I removed the 0-3 PSI gauge and plugged the hole. Maybe if I use a valve setup I'll be more inclined to blow it down.

I think if you are going to the chore of setting up the gauges, I would raise the whole control and gauges up well above the boiler waterline. Plumb in new parts coming out of the boiler and also a new straight pigtail. Place the setup you propose on top of that. That should raise it above the top of the complete boiler. I think the more you get them away from the water and heat, the better they work and longer they last.

Just a  thought.

- Rod

Jean-David Beyer

30 psi gauge?

Someone got there before me.

crash2009

Wika website, top 7

ways to wreck a gauge.  I am guilty of #2 pulsation.  Seven Reasons Pressure Gauges Fail

Preventing pressure gauge failure is of critical importance in the field. Many times there is no way of knowing why a gauge has failed. However, many times it is preventable. Here are seven reasons why pressure gauges may fail:

1. Mechanical Vibration, The oscillating, reciprocating or other periodic motion of a rigid or elastic body or medium forced from a position or state of equilibrium

 2. Pulsation, Rhythmical throbbing or vibrating; a periodically recurring alternate increase and decrease of a quantity (i.e., pressure, volume or voltage)

 3. Temperature, Degree of hotness or coldness measured on a definite scale

4. Spikes/Overpressure, The maximum pressure that can be applied to a pressure instrument without significantly affecting its reading accuracy; pressure significantly above what is usual or normal

5. Corrosion, Wearing away gradually, usually by chemical action

6. Clogging, Becoming filled with extraneous matter

7. Mishandling/Improper Use, Handling badly, misusing, or using wrongly or improperly

 Ways to Prevent Pressure Gauge Failure

 

There are many products and services that can prevent pressure gauges from failing. Gauge audits and [u][size=12][color=#0038a8]Best Practice Instrument Reviews[/size][/color][/u] are the best first line of defense. These reviews and audits will tell you which instruments are properly functioning and which ones should be replaced. There is a review of the gauges currently installed, gauges installed demonstrating unwanted conditions and of gauges installed demonstrating best practice. This review is provided by the team at the end of the review. Gauge audits and instrument reviews can be conducted to show and prevent mishandling and improper use of gauges.

 

A second line of defense could be to add a product or accessory to the configuration to alleviate the pressure or temperature. There are many products and services that can prevent pressure gauges from failing:

·                   Mechanical vibration can be avoided by choosing the correct pressure gauge for the application. Depending on the application a liquid filled gauge might be needed over a dry gauge.

·                   Pressure gauge snubbers avoid pulsation by absorbing pressure shocks and average out pressure fluctuations.

·                   Cooling elements prevent temperature spikes by protecting the pressure instrument from high or low process temperature. Air flow across heat exchanging fins reduces or increases the temperature of the system fill fluid to protect the pressure measuring instrument.

·                   Overpressure protectors are designed to avert spikes and overpressure damage. These protectors provide protection for pressure gauges against the effect of pressures exceeding their maximum pressure rating.

·                   Mini-siphons can stop corrosion by eliminating gauge whip and vibration as well as, protects the pressure gauge from harmful steam, hot vapors and liquids, and contains a unique inner chamber that reduces pressure surges and “water hammer”.

Diaphragm seals protect the gauge from slurry or viscous service and prevent corrosive and noxious process materials from reaching the gauge.

nicholas bonham-carter

gauge busters?

definitely mount that gauge on a vertical line extending well above the waterline. most of those gauges are rated for a certain amount of over-pressure before failure, and i do not have the website up so i don't know if you exceeded that or not. my guess is not, and that it is just debris in the line.

i do have doubts about the advisability of raising pressure up temporarily for blow down purposes-especially on old boilers. a sudden increase of even a few psi could cause some things to shift, and leak. blow-downs are good but i only rely on gravity from an elevated waterline, with no increase of pressure.--nbc

Rod

Blow Down?

Hi NBC -

    I'm inclined to agree with you. It may be that in raising the pressure above its normal operating level and blowing down, especially on an old boiler, the possible potential risks far out number the rewards. Of course this may be amateur thinking on my part as amateurs like myself, lacking the experience and knowledge, tend to be overly cautious.

The one thing I have noticed is that when I changed my return piping to copper that things seemed to stay a lot cleaner.

- Rod

crash2009

I think I found the problem

I shut it down and took the gauge off.  I blew lightly on the gauge and the indicator moves just fine, so I think the gauge is OK.  Then I looked in the T.  There was a little piece of Teflon tape stuck sideways across the inside of the T, across the opening of where the gauge goes.  I pulled it out with tweezers.  While I had the gauge off I blew in the T, thinking maybe it, or the pigtail was plugged, and it wasn't.  I expected to be blowing bubbles through the pigtail but it felt like it was empty.  The gauge was dry too.  Its been 6 or 7 hours since the last steam cycle. 

Rod

Gauge

The pigtail piping is so small that just slightly blowing on it emptied the loop. (Think soda straw)  Glad to hear your gauge was okay.

- Rod

TomM

darn thread tape!

use this n'stead

crash2009

Slowdown the Blowdown

Sounds like my technique is a bit too aggressive.  I will tone it down a notch or two.  Its just that it was real dirty and I thought it was normal to do what I did. Thanks for the warnings!  This building has had steam since about 1899.  First coal, then oil, and in about 1980 they put in natural gas, that boiler crapped out in about 2003.  They put in the same model, hooked up the same way, and hoped to sell the place before it blew up again.  We took over the place in 2007 and were not impressed with the way things were.  Twelve hundred dollar utility bills, electric heaters all over the place, everybody griping about how lousy the heat system is, etc.  While looking for some answers on the internet, I found you guys.  Rod, I remember you helping me figure out what to do amost a year ago.  TomM, it was shutting off on low water, thats probably how they blew up the 1st one.  Jpf, The boiler now has a dual drop header, Gerry, dual system risers, Dan, king valves and your books are great, 150 feet of mains are all insulated except for about 15 feet, while I had the insulation clothes on and the credit card in my hand I even insulated the wet returns.   Steamhead, We have 6 openings for main vents and a box full of Gortons for the rads.  Feels like I am ready for winter.  Thanks also to those that I can't remember how you helped!  

jpf321

great! did i miss a pic?

did i miss a pic of your new header? 

crash2009

Header

I thought you saw it already

Rod

I'm just a wimp!

On the Blow Off thinking- Please don't take what I said as a "warning", take as it is proof that I'm a big chicken!  The Pros here are probably rolling on the floor laughing at my caution. In my case I inherited a boiler that had been very badly abused and while it seems fine, I still tiptoe around it.

Nice job on your piping! That should make a big difference this winter.

- Rod

jpf321

looking nice ..

i had seen it already, but sometimes it's hard to keep track of em all. besides, it's always nice to showoff great work again right :-)

crash2009

Pat Giroux

out of Detroit did an excellent job on the piping.  Can you look over my numbers before I put the new vents on?

STEAM DOCTOR

joint compoud

Is the blue joint compound better for steam applications then other joint compounds?